Question
You are building a basic CPU with a classic RISC pipeline. Answer the following about a seemingly harmless instruction you may use, for 10 points each.
[10m] Name this instruction, which can be used to implement a pipeline stall in certain architectures, including x86 and MIPS (“mips”). A “sled” or “slide” is named for this instruction, which does nothing when executed.
ANSWER: NOP [or no-op or NOOP or no operation]
[10h] In x86, a NOP is implemented by completing this atomic action equivalent to three MOV instructions on the AX register. This action can be used to implement a semaphore in x86 because it activates a bus lock.
ANSWER: XCHG [or exchanging two registers; accept descriptions of swapping the contents of two registers]
[10e] An attacker may install a NOP slide in memory while exploiting this type of vulnerability where the bounds of allocated memory are exceeded. A common coding website is named for this effect occurring to a stack.
ANSWER: overflow [or overrun; accept buffer overflow or buffer overrun; accept Stack Overflow]
<KJ, Other Science: Computer Science>
Summary
| 2023 ARCADIA at UC Berkeley | Premiere | Y | 2 | 15.00 | 100% | 50% | 0% |
| 2023 ARCADIA at Carleton University | Premiere | Y | 3 | 16.67 | 100% | 67% | 0% |
| 2023 ARCADIA at Claremont Colleges | Premiere | Y | 1 | 30.00 | 100% | 100% | 100% |
| 2023 ARCADIA at Duke | Emory, Duke, Yale | Y | 4 | 12.50 | 100% | 25% | 0% |
| 2023 ARCADIA at Emory | Emory, Duke, Yale | Y | 4 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at Imperial | Imperial | Y | 5 | 14.00 | 100% | 20% | 20% |
| 2023 ARCADIA at Indiana | Premiere | Y | 5 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at Ohio State | Ohio State, Texas | Y | 3 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA Online | Maryland, Online | Y | 3 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at RIT | Premiere | Y | 2 | 15.00 | 100% | 0% | 50% |
| 2023 ARCADIA at Texas | Ohio State, Texas | Y | 3 | 10.00 | 100% | 0% | 0% |
| 2023 ARCADIA at WUSTL | Premiere | Y | 3 | 10.00 | 100% | 0% | 0% |
Data
| Berkeley B | Berkeley A | 0 | 0 | 10 | 10 |
| Stanford A | Berkeley C | 10 | 0 | 10 | 20 |
| McDouble West-Carleton | Waterloo | 10 | 0 | 10 | 20 |
| Ottawa A | Ottawa C | 0 | 0 | 10 | 10 |
| Toronto Ray of Sun in the Sky | Ottawa B | 10 | 0 | 10 | 20 |
| I will play anything with a buzzer in front of me | SGV Capital | 10 | 10 | 10 | 30 |
| Duke | James Madison A | 0 | 0 | 10 | 10 |
| James Madison B | North Carolina A | 10 | 0 | 10 | 20 |
| South Carolina A | North Carolina B | 0 | 0 | 10 | 10 |
| South Carolina B | NC State | 0 | 0 | 10 | 10 |
| Emory A | Georgia Tech B | 0 | 0 | 10 | 10 |
| Georgia Tech C | Georgia A | 0 | 0 | 10 | 10 |
| Georgia Tech D | Georgia B | 0 | 0 | 10 | 10 |
| Tennessee A | Georgia Tech A | 0 | 0 | 10 | 10 |
| Birmingham | Bristol | 0 | 0 | 10 | 10 |
| Cambridge B | Cambridge A | 0 | 10 | 10 | 20 |
| Edinburgh | Durham | 0 | 0 | 10 | 10 |
| Imperial A | Imperial B | 10 | 0 | 10 | 20 |
| Oxford | Warwick | 0 | 0 | 10 | 10 |
| Chicago A | Indiana | 0 | 0 | 10 | 10 |
| Chicago B | Notre Dame B | 0 | 0 | 10 | 10 |
| Illinois B | Purdue A | 0 | 0 | 10 | 10 |
| Notre Dame A | Vanderbilt | 0 | 0 | 10 | 10 |
| Illinois A | Purdue B | 0 | 0 | 10 | 10 |
| Kenyon B | Team 2 | 0 | 0 | 10 | 10 |
| Michigan B | Michigan A | 0 | 0 | 10 | 10 |
| Kenyon A | Ohio State A | 0 | 0 | 10 | 10 |
| Boston College | Zen and the Art of Buzzing | 0 | 0 | 10 | 10 |
| Farrellmagnetism | Ganon Evans Fan Club | 0 | 0 | 10 | 10 |
| MSU A and Friend | Arizona State | 0 | 0 | 10 | 10 |
| RIT | Cornell R | 0 | 10 | 10 | 20 |
| Syracuse+Rochester | Cornell MATLAB | 0 | 0 | 10 | 10 |
| Texas B | HCC | 0 | 0 | 10 | 10 |
| TAG Magnet: Taylor's Version | TAMU | 0 | 0 | 10 | 10 |
| Texas A | Texas C | 0 | 0 | 10 | 10 |
| Missouri A | SIUE | 0 | 0 | 10 | 10 |
| WUSTL H2O | Missouri B | 0 | 0 | 10 | 10 |
| WUSTL XYZ | Squidward Community College | 0 | 0 | 10 | 10 |